Low lift method and apparatus



April 5, 1969 w HAPMAN 2,931,306

LOW LIFT METHOD AND APPARATUS Filed June 7, 1956 5 Sheets-Sheet 1 INVENTOR. 93 flf/VAV W. Ha /441v I BY April 5, 1960 H. w. HAPMAN LOW LIFT METHOD AND APPARATUS 5 Sheets-Sheet 2 Filed June 7, 1956 UlllHllll 1| 11 11 ll 11 I! '1 II II IILLI INVENTOR. HENRY W HHPMHN April 5, 1960 H. w. HAPMAN 2,931,306

LOW LIFT METHOD AND APPARATUS Filed June 7, 1956 5 Sheets-Sheet 3 IN V EN TOR.

H TTORNE Y5 April 5, 1960 H. w. HAPMAN 2,931,306

LOW LIFT METHOD AND APPARATUS Filed June 7, 1956 5 Sheets-Sheet 4 INVENTQR. HZWRY V14 HEP/WEN HTT'ORAIZ'YS April 5, 1960 H. w. HAPMAN 2,931,306

LOW LIFT METHOD AND APPARATUS Filed June 7. 1956 5 Sheets-Skeet 5 m I42 Q "A m 5 M A INVENTOR. flzxvky V14 HAP/MN fiTTUF/VEYS United States Patent D F LOW LIFT METHQD AND APPARATUS Henry W. Hapman, Barry Township, Barry County, Mich, assignor of forty percent to Hannah Jane Hapman Application June 7, 1956, Serial No. 599,859

Claims. (Cl. 103-73) This invention relates in general to a lift method and apparatus for a sewage disposal system and particularly to a type of lift method and apparatus which is especially adaptable for use in areas where the underground water table is relatively high and, therefore, where a larger number of lift stations are required than under normal circumstances.

In the designing of a sewage disposal system, it is well known that such system will normally be arranged to take advantage of the natural slope or contour of the ground in which the system is located to provide sufficient fall to insure adequately rapid flow of the sewage materials through the system. However, where such fall is not available from the natural sloping of the ground, it is common practice to provide a series of lifting stations along a sewage disposal line and to provide between such stations whatever slope of the sewer pipe is necessary to insure proper flow of the sewage materials therethrough. Thus, in relatively flat land, such as occurs at many places in the Midwest, in the area around the Gulf of Mexico and others which are well known to the industry, the use of such lifting, or pumping, stations has long been accepted as standard practice.

Further, the use of such lifting stations is also commonly accepted even in locations having satisfactory natural slope to permit adequate flow through a sewage system where it becomes necessary to lift the sewage over or around a local obstruction such as a small hill orrocky terrain.

Under normal circumstances, it is possible to let the sewer pipes extend for considerable distances between pumping stations and thus even in relatively level ground, the number of pumping stations required may not be particularly objectionable. However, in areas where the Water table is relatively high, as less than about 8 feet below the surface of the ground, the number of lift stations required to operate the sewage disposal system must be greatly increased in order to secure the proper fall and yet maintain the sewer pipes above the level of the water table. If the sewer pipes are placed below the level of the water table, they have to be securely anchored or the water in the ground may displace them upwardly snfficiently to cause serious damage. Furthermore, the water surrounding the pipes will often seep into the pipes and flow along with the sewage, thereby greatly increasing the load of water being carried by the sewage system.

In present practice, the pumping systems and apparatus available are reasonably effective but are extremely costly, both in their original installation and in their maintenance. Even at best, many types of conventional equipment have serious disadvantages. For example, in most present installations, the lift stations are vented to atmosphere, which often results in the presence of objectionable odor around the lift station. Even where the present lift stations are provided with some means, such as stacks, for carrying away part of the odors, the constructions known to the prior art are still somewhat less than satis,

7 2,931,306 Patented Apr. 5, 1960 factory inasmuch as they must be opened up periodically to remove the debris which is collected by their screens. The numerous lift stations also often present an unsightly appearance unless they are built more attractively and this adds still more to a cost which is already so high as often to prevent the development of otherwise desirable sites. Obviously', the problems increase directly with the increase in the number of lift stations in the system, and these numbers increase rapidly in areas with a high water table. 7

In addition to the cost of the installation of said pres: ently existing pumping, or lift stations, the cost of operating, inspecting and maintaining such stations, including the removal of debris from the screens thereof, is correspondingly high. As a result of the odor, high cost and frequent unsightly appearance of the presently existing stations for lifting sewage, the further development of some otherwise habitable areas has been made extremely costly.

Insofar as I am aware, there has been no inexpensive apparatus previously available for removing both solids and liquids of the character here involved from a low level to a higher level, which can be effectively submerged in the materials being lifted. Thus, the apparatus controlling the lift operation must be disposed at one location, while associated apparatus in contact with the sewage must be in another location. As a general proposition, the presently existing devices are comprised of a tank covered by a screen through which the sewage is caused to pass, the large debris being collected by the screen. The liquid and smaller solid materials are then sucked through a pipe and carried to a pump, which drives the materials to the higher level.

Users of this type of lift station are caught between two dilemmas. Either they must carefully screen out all of the materials which .are likely to cause damage to the impeller blades of a conventional type of pump having minimum clearance between the impeller and the housing, or they must use a pump having very large clearances so that large, solid materials can be passed through the pump without damaging the internal parts thereof. However, these pumps with large clearances have low efliciences, relatively speaking, and, therefore, must be of large size in order to meet the required capacity. This, of course, results in both high original cost and high power inputs to the pump, with corresponding expense for the whole sewage project. If the high efiiciency type of pump is used, then, of course, it' is necessary that the screens which remove the objectionable materials, such as branches of trees, tin cans, bottles, rags, etc., from the sewage, be cleaned regularly in order to permit. the proper operation of the sewage system.

In order to overcome some of the problems involved in the presently existing types of commonly used mechanical pumping station discussed above, air lift stations have been offered to the trade. In these devices, the sewage material is often dropped into a well after which it is forced by air pressure up into the higher level for discharge into the next line of sewer pipes. However, it is still necessary to remove the heavy materials from the well periodically, because the pressures available are not great enough without entirely prohibitive cost to move such materials to the higher level. Furthermore, the structure is not only costly, but it is not suitable for use in areas where the table of water is high, for reasons that it would require tremendous weight to keep it anchored in the ground against the upward pressure of the water surrounding the tank.

Accordingly, it has been a primary purpose of this invention to provide a relatively small, low cost, positively acting, completely self-contained, low lift station, particulzirlyadapted for use in areas where the water table is relatively high, as within 6 or 8 feet of the surface of the ground, whereby both. solids and liquids can be handledywithout needfor periodic .cleaning of the station andl'withoutvneedformore than casual, periodic, inspection of the operating mechanism- A further object of 'this invention is the provision of a, low lift station, asaforesaid, which can operate substantiallycontinuously, or periodically as the case may require, which can,. if desired, be so constructed that it extends very little, or not'at all, above the surface of thegroundwhere it is installedywhichcan-be entirely operated by a single prime mover, but .whichcan, where theprincipallprime mover is electrically driven, alternatively be coupled to an auxiliaryengine for use in the case ofa failure inthe electrical supply. a a

.A'further object of this invention is the provision of 'a lift station,-as aforesaid, wherein the sewagelifting parts can be completely submerged within the sewage material being, lifted, are self-lubricated by the sewage materials being lifted, can be easily and readily replaced and repaired by unskilled persons having average ability in such matters, are extremelyrugged in construction, are capable of sustaining material damageand still continue to operate without serious loss of efficiency, are capable of handling any typeof material which is likely to fall into a sewer pipe and be conveyed therethrough, and which require very little attention and cost very little to operate and to maintain. i A further object of this invention is the provision of a lift station, as aforesaid, which is relatively easy to install,'which can be completely. hidden from ordinary view, which canrbe completely and totally enclosed at all times, thereby avoiding noxious odors, and which is 'jeflicient in operation. v

Other object's and purposes of this invention will become apparent to persons acquainted with this type of equipment upon reading the following specification and examining the accompanying drawings, in which:

Figure 1 is a side elevation view of a low lift, sewage pumping station embodying my invention. 1

Figure 2 is an infiuent, or left end, elevation view of a of Figure 3. r I a Figure 5 is a sectional view taken along the line V--V of Figure 3.

Figure dis a broken, sectional view taken along the line VI VI of Figure 3. a J

Figure 7 is a sectional view taken along the line VII- VII of Figure 3. Y i 7 Figure 8 is a sectional view taken along the line VIII VIII of Figure 7.

Figure 9 is a sectional view taken along the line IX IX of Figure 8. l Figure 10 is a broken,-side elevation view of a low lift sewage pumping station embodying a modified form of my invention. M Figure 11 is a left end elevation view of thestructure appearing in Figure 10.

Figure 12 isfa sectional view taken along the line XII- XII of. Figure 10. t

Figure 13 is a modified, low lift station adapted for moving sewage over an obstruction adjacent the low lift station and in the path of the sewer system with which the station is being used. I

Figure 14 is a central cross-sectional view of an alternate. pump'tube and endless conveyor therewithin.

FigurelS is a sectional view taken along the line XV- XV ofFigure 14. e

For the purpose of convenience in description, the t erms upper," lower, and derivatives thereof,-will*have reference to a low lift station and parts thereof as appearing in Figures 1, 2, 10 and 13. The terms influent end and effluent end will have reference to the leftward and rightward ends, respectively, of the low lift station as appearing in Figures 1, l0 and 13. The terms inner, outer, and derivatives thereof, will have reference to the geometric center of said low lift station and parts associated therewith.

I v General description In order -to meet the objects and purposes set forth above, as well as others incidental thereto, I have provided a low lift station 10 (Figures 1, 2 and 3) which, in one particular embodiment of my invention, is comprised of a relatively low collection tank 11 and a relatively high discharge chamber 9. An infiuent pipe 12 communicates with said tank 11 near the lower, left hand end thereof, and an efiiuent pipe 13 communicates with said chamber through its right hand end. One end of an arcuate, substantially U-shaped tube 14 communicates with said tank .11 at a low point or sump 15 therein, and the other end of said tube extends through the left end wall of said tank 11 at a point spaced from said one end of said U-shaped tube 14. A materials passageway, such as the pump tube 16, is disposed within the tank 11 and communicates between the sump 15 and the chamber 9. An endless conveyor 17, which may be of a type similar to that shown in my Patent No. 2,573,905, slidably extends through both the U-shaped tube 14 and the pump tube 16. The conveyor 17 also extends around a sprocket 18 rotatably supported in the upper end of the lift station 10 for rotation by a prime mover 19. A bafile plate 21 whichoprovides the left wall for the chamber 9 snugly engages and encircles the upper end of the pump tube 16 for directing materials ejected from said pump tube into said chamber and thence into the adja- .cent end of the efiiuentpipedl The lower end of the pump tube 16 is provided with an opening 22 through which the materials dumped into the tank 11 from the infiuent pipe 12 may be introduced into the pump tube 16 for movement upwardly therethrough by the conveyor For convenience in'descriptiomthe ueshaped tube 14, the pump tube 16, the conveyor 17 and the sprocket18 may hereinafter be referred to as the liftmechanism 23. For purposes appearing hereinafter, the lift station 10 may also be provided with an auxiliary; lift mechanism 24 (Figures 2 and 4) including aU-shaped tube 14a, a pump tube 16a, a conveyor 17a, :and a sprocket 18a, each of which may be substantially identical to the corresponding parts inthelift mechanism 23. Where the principal prime mover '19 is an electric; motor, an auxiliary prime mover 25, such as the gas engine shown in Figure 4, may be coupled ,yvith the prime mover 19, as through the shaft 26suppor-ting the sprockets 18 and 18a; r r a a Detailed construction As shown in Figures 1 and 3, the lift station 10 is arranged for passage of the sewage materials from left to right and it is relatively narrow crosswise of the general direction of flow of the sewage therethrough. Said tank 11 has a pair of substantially parallel side walls 31 and 32, a pair of end walls 33 and 34, and a bottom wall 36, all of which are preferably, but not necessarily, fabricated from a relatively rigid and durable material, fsuch a's steel plate, and which are secured to each other in a relatively water-tight fashion by any convenient, conventional means, such as by welding. The bottom wall 36 of the tank 11 has an upper surface, which in this particular embodiment, slopes downwardly and rightwardly from the left end wall '33, where it engages the lower edge of thei'right wall 34 to'form the sump 15. The influent pipe 12 is secured inany convenient manner to the left endrwall 33' nearthe bottom wall 36' and communicates w th he c ect o ank 11 point pr e bly jacent to the sump 15. As appearing in Figure 3, the right wall 34 is inclined upwardly and rightwardly, and is advantageously positioned approximately at right angles to said bottom wall 36 for ease of construction and assembly.

The side plates 31 and 32 (Figures 3 and 6) extend rightwardly beyond the tank 11 to form the side walls 37 and 38 of the chamber 9 in this particular embodiment. Said chamber has a right end wall 39 and a bottom wall 41, said latter having a substantially V-shaped crosssection provided by the inwardly and downwardly sloping plates 42 and 43, which are secured, in any convenient manner, along their upper edges to the opposing surfaces of the side walls 37 and, 38, respectively. The leftward ,end wall of the chamber 9 is provided by the upwardly and leftwardly inclined bafiie plate21, the upper edge of which is preferably arranged in water-tight engagement with the top plate 45, which covers both the tank 11 and the chamber 9. Said bafile plate 21 is preferably disposed substantially parallel with the bottom wall 36 and is in substantially water-tight engagement with the side plates 31 and 32, the upper edge of the end wall 34, and the bottom wall 41.

The effluent pipe 13 is secured to the end wall 39 of the chamber 9, such as by welding, near the lower edge thereof and communicates with the discharge chamber 9 at a low point between the sloping plates 42 and 43. Thus, since the effluent pipe 13 will normally have a slight downward slope away from the discharge chamber 9, in a substantially conventional manner, any materials, particularly of a primarily liquid nature, which are within the discharge chamber 9 will tend to flow directly into the efliuent pipe 13.

A suitable guideway, which is in this embodiment a pump tube 16 (Figures-3 and 5), of circular cross-section, is disposed parallel with, and near to, the right end wall 34 and extends between the bottom wall 36 and said bafile plate 21. The upper end of the pump tube 16 is provided with an integral, annular flange 46 for removably securing said pump tube to the lower side of the baffle plate 21, as by means of bolts 47, in registry with a port 48 extending through said baflie plate 21. The lower end of the pump tube 16 is snugly, but removably, received into an annular guide 49 (Figure 5) secured in any conventional manner to the upper surface of the bottom wall 36. The said lower, open end of the pump tube 16 is in registry with a circular port 51 in the bottom wall 36, which port is of substantially the same internal diameter as the internal diameter of the pump tube 16.

The opening 22 in the side wall of the pump tube 16 is preferably disposed adjacent to the lower end of said tube and preferably faces the left end Wall33. Although the actual size of the opening 22 may vary substantially, depending'upon the circumstances, such as the materials encountered, it will normally extend approximately half way around the circumference ofthe tube and will preferably in many embodiments be approximately equal in length to the diameter of said tube 16. In any event, the low point in the liquid level 50 (Figure 3) will normally be about even with the upper edge of the opening 22.

The U-shaped tube 14 (Figures 2 and 3), which may have a slightly larger internal diameter than the internal diameter of the pump tube 16, is provided with an annular flange integral with one end thereof, whereby the said onee'nd of said LJ-shaped tube is secured, as by means of thebolts 53, to the lower surface of the bottom wall 36 is-registry with the portSl. Said U-shapedtube 14 extends in an arcuate path downwardly and then back upwardly to a point above the infiuent pipe 12 where it passes through a port 54 in the end wall 33 located above the influent pipe 12. In this particular embodiment, said U-shaped tube has a relatively straight upper portion 55, which passes through said port 54 and is sealed in position, as by welding. A bracket 56 may, if desired, lie-mounted upon the inner surface of the end wall 33 f r engaging and assisting in supporting the straight portion 55. Said straight portion 55 preferably has its inner end flared outwardly and its axis is preferably arranged to converge with the axis of the pump tube 16 at a point located substantially above the top plate 45 for reasons appearing hereinafter. The exact location of the port 54, the length of the straight portion 55, the radius of curvature in the U-shaped tube 14 are all matters of design which can be, and often will be, varied according to the demands of the circumstances encountered. Both the pump tube 16 and U-shaped tube 14 are preferably made from a relatively rigid and durable material, such as metal pipe.

As shown in Figures 3, 4 and 5, the endless conveyor 17 extends through the U-shaped tube 14, the pump tube 16, and around the sprocket 18, which sprocket is mounted upon, and rotatable with, the. sprocket shaft 26. The shaft 26 is, in turn, rotatably supported, as by means of the bearings 57, upon the top plate 45 and supports a pair of sprockets 58 and 59 at the opposite ends thereof for rotation therewith. The pulley 53 may be connected in a conventional manner to the gear reducer 60, which is in turn driven by the motor 19. The shaft 26 is provided with a clutch 61 intermediate the ends thereof, whereby the two portions of said shaft on opposite sides of said clutch can be caused to rotate together or independently. As shown in Figures. 3, 5 and 7, the endless conveyor 17 may be comprised of an endless link chain 62 upon which a plurality of uniformly spaced flights 63 arev mounted for movement by said chain through the tubes 14 and 16. These, flights will fit, snugly, though slidingly, within the tube 16 and will accordingly be of whatever cross-section is required to effect such snug fit. In the present embodiment, the flights are circular in cross-Section, or disk-like, but where the. tube 16 is of other internal cross-section, such as rectangular, the flights 63 are modified accordingly.

Thus, in this particular embodiment (Figures 7,. 8 and 9), each flight 63 is comprised of a cylindrical spacer ring 6 disposed between a pair of coaxial, circular pressure plates 65 and 66,. which are somewhat larger in diameter than the spacer ring 64. The flights 63' are connected by any convenient type of. flexible connector, such as articulated linkage, flexible cable with suitable spacers between flights, or even knotted rope. In. this embodiment utilizing articulated linkage, a center link. 67 of the chain 62 has a pair of parallel'pin openings68land 69 at opposite ends thereofand is secured,.as by welding along one lateral, lengthwise edge thereof, to.the inner surface of the spacer ring 64. 'Such securement is preferabiy midway between the center lines" of the pin openings 68 and 69. Appropriate link openings Hand 72 are provided through the pressure plates 65 :and .66.for slidably and snugly receiving the opposite ends of Lth'e center link 67 therethrough when said pressure plates are coaxial, both with each other and with the spacer-ring 6'4, and disposed adjacent to the opposite sides of the"sai spacer ring 64. Said pressure plates 65 and 66-a'reprovided with a plurality, here five, of corresponding and coaxial bolt openings 73, through which the machine bolts 74 extend. Said bolt openings 73 are preferably arranged so that said bolts 74 will all extend through-the open center of the spacer ring 64 near to, and atsel'ected intervals along, the inner surface of the spacer ring64.

A plurality, here three, of preferably identical, resilient and flexible wear rings 75 are'removably supportedupon, and encircle, the spacer ring 64 between the pressure plates 65 and 66. Said rings are slightly larger in di ameter, as for example, /2 inch in the case of a- 9 inch diameter ring, than the diameter of the pressure plates 65 and 66. fie axial thickness of the three rings 75, when placed upon the spacer ring 64, is slightly 2', such as inch for example, than the width or the axial thickness of the spacer ring 64. Thus, as the peripheries of the rings 75 wear down through use,

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said rings may be caused to expand radially by further Figure 9, along a radius thereof in order to provide for easy replacement of worn out rings.

When first installed in a system, the wea'r'rings 75 will be of-such diameter, in the absence of any material pressure being applied thereto by the pressure plates f 65 "and 66, that'they will snugly, but slidably, embrace the-internal walls of the pump tube 16 to provide a substantially water-tight seal between each flight and said pumptube when said flights are substantially coaxial tlrt't'ere'with.

In this particular embodiment, the adjacent ends of the 'centerlinks on a pair of adjacent flights 63 are pivotally connected by means, such as the pins 77, between the corresponding ends of a pair of parallel side links 78 and 79; Resilient grommets 81 (Figure 7), which encircle the link pins 77, are disposed between the opposing surfaces of the side links 78 and 79 and the center link 67, and also adjacent to the outside surfaces of said side links. [Said grommets are held under compression by, and between, a pair of washers 80, which encircle the pins 77 and are held with respect thereto by the snap rings 80a placing the grommets 81 under compression, prevents the entrance of abrasive materials, such as dirt, between the contacting surfaces of said links 67, 78 and 79 and therebyprevents what would otherwise be a very severe wear problem. It will be recognized that said center'links and said side links can be made in a variety of sizes and shapes to effect any desired spacing between adjacent .flights 63; It will also be recognized that other center links 67a, which do not support a flight 63, may be inserted.at intervals along the chain 62, thereby providing further means of adjusting the space between adjalcent flights. T

The actual space between said flights 63 in any particular installation may be, and often is, dependent upon one or more of a variety of factors. Where, as here, the flights are being used as unidirectional pistons in the pump tube 16, theamount of drag, hence the number of flights in engagement with the interior wall of the .pump tube 16, may be limited by the available or reasonably availablepower source for driving the sprocket 18, particularly where the pump tube 16 is relatively long. However, this can be overcome to some extent by enlarging the internal diameter of the pump tube 16 in a portion of said tube spaced from the lower end thereof, and thereby reducing the amount of said drag. However, where the tube16 is used to lift liquids efliciently, it 'willEbe essential that at least two adjacent flights, selected anywhere along the chain 62, can be, and will be, engageable simultaneously and snugly with the internal walls of said pump tube 16 near to the opening 22 therein. Any less contact between the flights and the lower end of said pump tube 16 would impair the utility of the pump tube 16 as an eflicient conveyor of liquids. Under normal circumstances, it would be advisable to have at least three, and preferably four or five, flights 63 in simultaneous, snug engagement with the interior walls of the pump tube 16 adjacentto the lower end of said tube at all In such case,,any impairment of the seal between one, or even two, adjacent flights 63 would not materially reduce the operating efliciency 'of the lift mechanism 23. It will be recognized, in this connection, that sewage often contains rather large and sturdy objects, such as containers and chunks of wood ormetal, which are capable of damaging or disfiguring individual flights 63 when said lift mechanism 23 is being used under extremely severe operating conditions.

As a general rule, it has been found advantageous to build the greater strength of the mechanism 23 in the chain 62 and the pump tube 16 rather than in said flights. i rims, when the mechanism =2: is'xps e T in harsh treatment, the flights 63 will rupture or give way before the 'lift mechanism 23 is jammed or otherwise madecompletely inoperative. This recognized existence of'large, solid objects, such as metal containers, in the sewage being handled also has a bearing upon the spacing between adjacent flights 63. That is, the spacing between flights should be sufiicient to accommodate 01' receive therein any large objects which are reasonably expected to be found in the sewage."

As shown in Figure 3, the sprocket 18 isprovided with teeth 83 which will extend into the slots 84 (Figure 5) between the side links 78 and 79 for driving the chain 62. Due to the fact that the chain 62 is offset with respect to the axis of the flights 63, said chain 62 will automatically tend to orient itself as it moves around the sprocket 18, as well as when'it moves through the arcuate' portion of the U-shaped tube 14 in an established manner. 5

The upper, flared end of the straight-portion 55 of the U shaped tube 14 is intentionally spaced from the sprocket 18 so that the force of gravity acting upon the portion of said chain between said U-shaped tube and said sprocket can be utilized to impose a resilient tension upon the chain 62. The flared end on said portion 55 provides guide means for directing the flights 63 into said tube. Openings 85 and 86 may be provided in the top plate 45, whereby the flight conveyor 17 can move upwardly and downwardly, respectively, through said openings. I

The auxiliary lift mechanism'24 (Figures 2 and 4), including a. U-shaped tube 14a, a pump tube 16a 'a flight conveyor 17a, and a sprocket 18a, may be disposed within the liftstation 10 in substantially the same. manner as described hereinabove with respect to the left mechanism2-3. As shown in Figure 2, the mechanisms 23 and sprocket shaft 26 near that end thereof remote from the sprocket .18. In a similar manner, additional auxiliary lift mechanisms 24 could, if necessary, be provided within the lift station 10.

The sprocket 59 (Figure 4), located near said sprocket 18a, may be connected to an alternate source of power,

such as a gasoline engine 25, which is also mounted upon the top plate 45 near to. the motor 19. A low metal housing 87 may be provided for covering the motor 19, the engine 25, the gear reducer 60, and parts associated therewith. Suitable access doors88 (Figure 3) may be provided in the upper surface of saidcover housing 87 for inspecting and maintaining the driving mechanism and the prime movers. Inspection doors, such as that shown at 89 in Figure 3,- may be provided in the top plate 45 for inspecting the interiors of the collection tank 11 and discharge chamber 9. However, it will be observed that, excepting for such moments of inspection, the lift station 10, including the cover housing 87, may be completely'elosed and substantially sealed against the escape of noxious odors from the sewage handled thereby. The grade level may be substantially coplanar with said top plate 45, as shown in Figure 1, or if preferred, the entire lift station 10, including the cover housing 87, may be buried up to the top level of the housing 87'.

' Where the water table is relatively high, and there is an occasional possibility for the water level to rise above the low point of the U-shaped tube 14 or perhaps even be above the low point on the tank 11 in extreme cases, it may be desirable to anchor the lift station'lfl upon a concrete base 91 by means, such as the structural brackets 92. The base 91 may, if desired, be comprised of prefabricated concrete slabs, which are easily and quickly installed. The U-shaped tubes 14 and 14a may be anchored upon said base 91 by means of anchoringdevices 93 and 93a (Figure 2). a a t It may; become desirable, under some circumstances,

amma to provide a small pump house, such as that indicated in broken lines n94 in Figure 1, at the site of the lift station 10. In such case, said pump house can be supported at least partially upon the upper plate 45, thereby eliminating the need for both the cover housing 87 and, in all likelihood, the base 91.

Operation Having installed the lift station 10 with its influent pipe 12 connected to the low end of one sewer pipe, and with its eflluent pipe 13 connected to the high end of another sewer pipe, and having connected the prime mover, such as an electric motor 19, to a source of energy and to the sprocket 58 on the shaft 26, the lift station 10 is ready for operation. i

By proper adjustment of the clutch 61, the lift mechanisms '23 and 24 may be operated either independently or together. This invention contemplates the possibility of remotely controllingthe clutch 61 in a plurality of lift stations, similar to that disclosed herein, from a central station. Thus, when weather or other conditions indicate need for additional pumping facilities, the auxiliary lift mechanism 24 could be brought into service immediately and without difiiculty.

The flight conveyor 17 will be moved by the sprocket 18, in a manner obvious from the above description, through the U-shaped tube 14 and the pump tube 16 past the opening 22 in said pump tube. As the sewage moves into the collection tank 11 from the influent pipe 12, it will move down the sloped bottom wall 36 into the sump 15 cr eated thereby. Any solids which reach the conveyor 17 will immediately be moved upwardly thereby through the pump tube 16 and thence into the chamber 9. The liquids will collect in the sump 1 until they are about even with the upper edge of the opening 22. The pumping action of the conveyor 17 and tube 16 will then begin totake eflect, whereby said liquids will also be moved into the'chamber 9. Both the solids and the liquids will be deposited onto the batfle plate 21 and thence flow through the discharge chamber 9 into the adjacent end of the efiiuent pipe 13. Because of the nature of the flight conveyor 17, and the pump tube 16 associated therewith, both liquids and solids of all sizes and shapes capable ofpassing through the influent pipe 12 into the sump 15 will be moved upwardly through the pump tube 16.

Under normal circumstances, the flight conveyor 17 will move through the U-shaped tube 14 and pump tube 16"ata relatively slow rate of speed, such as 25 feet per minute, while still producing a highly eflicient pumping act i o n through said pump tube 16. For example, it is possible to move liquids or liquid suspended materials through a pump tube having a 9 inch inside diameter at th'r a te of 70 gallons per minute, while operating the flight conveyor 17 at a relatively normal linear speed of 25 feet per minute.

In the event that the Wear rings 75 on any flight 63 become sufliciently worn that the flight loses some of its pumping efliciency, these Wear rings can be easily and quickly caused to expand, thereby providing a sea] as good as was initially present, simply by tightening the bolts 74 Under normal circumstances, said wear rings 75 can be submitted to several of these expansion adjustments before they need be replaced. When this occurs, or alternatively, when the wear rings are damaged or disfigured during the operation of said flight conveyor 17, said wear rings can be quickly and easily removed from their particular flight 63 simply by loosening the bolts 74 and removing said rings 75 from their position upon the spacer ring 64. Under normal circumstances, it is found advantageous to space the split lines 76 on the three adjacent wear rings 75 at 120 intervals around the flights in order to remove any possibility of a loss in eflicient operation. Replacement of said wear rings can be effected simply by raising one of the access doors 88 on the cover housing 87.

In case any particular flight is so badly damaged that it cannot be readily repaired without removalfrom the flight conveyor 17, such removal can be easily and quick- 1y effected by removing the link pins 77 from the opposite ends of the center link 67 associated with the damaged flight, removing that flight and replacing it with a new flight, after which the pins 77 are again returned to their former position. This repair can also be effected without going below the level of the top plate 45.

Because the opening 22 in the pump tube 16 is located adjacent to the bottom wall 36 in the sump 15, the lift mechanism 23 automatically and continuously prevents the collection of any material amount of sediment in the bottom of the collection tank 11. The liquids in the sewage automatically lubricate the engaging surfaces between the conveyor flights 63 and the walls of the tubes 14 and 16. The space between the sprocket 18 and the upper, flared end of the U-shaped tube 14 permits the upper course of the flight conveyor to droop between these points under the force of gravity and thereby automatically impose a proper tension upon the chain 62.

The operation of the lift mechanism 24, and its associated parts, may be substantially identical to the operation or" the lift mechanism 23, described hereinabove. If it becomes desirable to operate the lift mechanisms 23 and 24 simultaneously, such can be effected by engaging the clutch 61. In the event that the source of power for the prime mover 19 fails at any time, the auxiliary prime mover 25 can be immediately placed in operation to drive the lift mechanism 24 separately or both lift mechanisms 23 and 24 together, depending upon the operative condition of the clutch 61.

Modified structures As shown in Figures 10 and 11, it may be desirable under certain conditions of anticipated heavy-duty operation, to provide a modified lift station 101. The flight conveyor 102, which may be substantially identical to the flight conveyor 17 described in detail hereinabove, is primarily intended to move solid materials only from the sump at the lower end of the collection tank 103 upwardly into the discharge chamber 104 of the modified station 101. In such case, the lower, or upwardly moving, course 106 of the conveyor 102 is preferably unincased within the tank 103. As shown in Figure 12, the inclined end wall 107 of the tank 103 has a cross-section shaped like an upwardly expanding U for providing the guideway which partially surrounds and snugly engages approximately the lower half'of the flights 109 on said conveyor 102 as they move upwardly along said end wall 107. Thus, any solid materials which enter the collection tank 103 through the influent pipe 111 and flow into the sump 105 will be engaged by the flights 109 and moved upwardly along the end wall 107 until they pass through a port 112 in the downwardly and rightwardly sloped baflie 113, which separates the collection tank 103 from the discharge chamber 104. As in the case of the lift station 10, the flight conveyor 102 passes around, and is actuated by, the sprocket 114, after which it then enters the upper end of the U-shaped tube 115, which may be substantially similar to the U-shaped tube 14 of the lift station 10. The force of gravity acting upon the portion of the conveyor 102 between the sprocket 114 and the U-shaped tube 115 is suflicient to exert a proper tension upon the entire flight conveyor 102.

Because the flight conveyor 102 is primarily concerned with the removal of solid materials from the collection tank 103, a pump 116 is suspended within the upper part of the sump 105 for the purpose of removing the liquids from the tank 103. Said pump 116 is operably connected to, and suspended from, a motor or other prime mover 117 by the elongated casing 118. Said motor 117 is mounted upon the side wall of, and is supported within the upper end of, the tank 103, where it will be at all times well above the liquid level within the tank 103. The outlet of the pump 116 is connected to the lower 'end of a discharge tube 119, which extends upwardly the discharge chamber 104. Thus, the liquids discharged from the tube 119 may be used to remove residual solid materials from the flight conveyor 102 as it passes through the-discharge chamber 104.

A-port' 121 is provided in the baffle 113 for the return of the flight conveyor 102 from the sprocket 114 to the U-shaped tube 115. The port 112 in the bafile 113 is intentionally made oversize with respect to the diameter of the flights 109 in order to permit the easy passage through said baflie 113 of oversize pieces of solid material being moved up the wall 107 by the flight conveyor 102. A flap 122 of flexible, waterproof material, such as rubber impregnated cloth, is mounted upon the upper surface of the baflle 113 for the purpose of cover- "ing that part of the port 112 which is in excess of the opening needed for the flights 109, and thereby preventing the liquids passing through the tube 119 from splashing back into the tank 103. The discharge tube 119 servesthe additional purpose of urging the solid materials moved into the discharge chamber 104 by the flight conveyor 102 into the open, adjacent end of the diluent pipe 123. V A float-type control mechanism 124 may be provided "on themotbr 117 for automatically initiating the operation of the motor 117, hence the pump 116, when the liquid reaches a selected upperlevel in the tank 103, and for automatically shutting off the motor 117 when the liquid drops to a lower level in the tank 103. It will be recognized that the flight conveyor 102 will tend to prevent the accumulation of any substantial amount of sediment or solid materials within the sump 105. Thus, the pump 116 can be disposed relatively close to the bottom of the tank 103 and thereby maintain the liquids within the tank 103 at a relatively low level at all times without endangering its working parts. Because of the fact that the conveyor 102 is specifically provided for removing the solid materials from the collection chamber 103, the pump 116 may be of the close tolerance, high efficiency type specifically designed for handling liquids only. The sprocket 114 may be driven in any convenient manner, such as that disclosed and described hereinabove with respect to the structure shown in Figures 3 and 4.

Figure 13 illustrates a further modified lift station 128, wherein the discharge chamber 129 is spaced a substantial distance from the collection tank 130, for the purpose of moving sewage materials over an obstacle in the path of their desired flow, such as a rise in the terrain. The'collection tank 130 of the lift station 128 communicates with the low end of an influent pipe 131 and is provided with a U-shaped tube 132 disposed externally thereof in substantially the same manner as disclosed hereinabove with respect to the structure'shown in 'Figure 3. However, the upper end of the U -shaped tube 132 is provided with an elongated straight portion 133, which extends completely through the collection tank 130 and the ground, or other media, disposed between the tank 130 and the discharge chamber 129, and communicates With the interior of the discharge chamber 129. The pump tube 134 is also elongated and communicates between thesump 127 in the lower end of the tank 130 and the discharge chamber 129.

Where the tank 130 and chamber 129 are spaced a considerable distance from each other, said pump tube 134 and straight portion 133 of the U-shaped tube 132, are preferably substantially parallel. However, it will be recognized that, because of the flexible nature of the flight conveyor 135, which may be'substanti'ally identical pump tube 16 (Figure 3).

o 12 I to the flightconveyor 17 disclosed hereinabove, said pump tube 134 and straight portion 133 may be bent or curved through a variety of convolutions, not necessarily parallel with eachrother, providing only that such' bends are not unreasonably sharp, to permit said tubes,132 and 134 to bypass obstacles between the desired locations of the chambers 129 and 130., ,Such obstacles might be in the form of other pipes, tree roots, or the like. The lower end'of the pump tube 134 disposed within the lower end of the collection chamber 130 is provided with an intake opening 136 which, like the opening 22 in the pump tube 16 (Figure 3), is arranged for receiving both solid and liquid sewage materials which flow into the tank 130 from the adjacent end of'the infiuent pipe 131.

Under normal conditions, at least a substantial portion "of the pump tube 134, preferably adjacent to the opening 136, will have substantially the same inside diameter as the outside diameter of the flights 137 on the flight conveyor 135, in order to effect the desired pumping action in a manner discussed in detail with respect to the 7 On the other hand, the U-shaped tube 132 and the upper straight portion 133 thereof will normally have an inside diameter slightly larger than the normal'outside diameter ofthe flights 137, thereby reducing the resistance to movement of said flight conveyor 102 as it returns through these tubes to the tank 130. 'Materials discharged from the pump tube 134 will flow into the discharge chamber 129 and thence into the adjicent end of an efiluent pipe 138 to take up, and continue, their movement through the sewer system.

It will b recognized by reference to Figures 10 and 13, that the structure of Figure 13' can be easily modified, as

by increasing the diameter of the pump tube 134 and adding the liquid pumping mechanism disclosed in Figure '10, to'provide a lift station wherein the liquids and solids are moved from the collection tank 130 upwardly into the discharge chamler 129 through substantially independent conduits. It will also become apparent that a low lift station, of the type disclosed in Figures 3 and 10, maybe adapted to overcome a variety of problems, suchas the'one illustrated in Figure 13, while continuing to operate fundamentally asfpart of a low lift sewage system. a c

The lift stations 10, 101 and 128 have been described, for the sake of convenience, with their influent pipes at one end' and'their' effluent pipes at the opposite end. Obviously, this specific arrangement is not essential to the invention. As indicated by the broken line circle 139 in Figure 3, the influentpipe could enter through the side wall of the tank 11; Likewise, as indicated by the broken line circle 140 in Figure}, the efiiuent pipe could also discharge through a sidewall.

Further, it is obvious in view of the foregoing that the conveyor flights, the guideway against which the flights operate, and the U-shaped tube 14, or the counterparts of these elements in the several forms of the invention, are here shown as of circular cross-section for illustrative purposes only. These parts can be of any desired crosssectional shape, particularly including rectangular, and

the conveyor flights can be connected by many other forms ofiflexible connectors. Asillustrated inF-igures l4 -andl5, the pump tube 16b has a rectangular cross-section and'the conveyor 17b is comprised of a plurality of rectangular flights 63a sleeved upon :a ,cable 62a with resi lient spacers 142 between flights; Further types of fllght conveyor constructions are detailed in United States PatentN0s.'2,5'55,338; 2,595,941; and 2,667,962. Hence;

which lie within the scopeoi' such invention. are fully contempiated unless spec lically stated to the contrary in the appended claims.

" I claim:

1. An apparatus for raising sewage materials comprising both liquid and solid components troriiorie level to a h gherlevel, comprising in combination: a collection tank having a sump and an influent port nearand above said sump,said influent port being "at said one level; a discharge chamber offset horizontally from said sump and having a floor disposed upwardly of said influent port and having an efliuent port ad acent to said floor, said effluent port being at said higher level; and inclined upwardly extending guideway, extending from said sump to said chamber, said guideway being open at its lower end so that sewage materials within said sump may enter thereinto, the cross-sectional shape and area of said guideway being substantially equal throughout its length; an inclined, endless flexible conveyor having a course extending from said sump to said chamber along and within said guideway and having a curved portion disposed outwardly of, and at least partially bCiOW, said tank, said conveyor including a flexible connector and a plurality of spaced and substantially identical flights slidabiy fitting Within said guideway for moving sewage materials tnerewithin upwardly to said discharge chamber; drive means for eflecting upward movement of said course along said guideway and tubular casing means fully enclosing and guiding the entirety of said con eyor located outwardly of said tank and said discharge chamber.

2. The device defined in claim 1 including a pump having its intake in said sump spaced at selected distance above the lower end of said guideway, a pipe connected to the discharge of said pump extending upwardly and discharging into said discharge chamber.

3. The device defined in claim 2 wherein said pipe discharges against and through said conveyor immediately above the upper end of said guideway.

4. Apparatus for raising sewage materials, comprising: a collection tank having a bottom wall defining a low end and an inlet port above, but near to, said low end; a discharge chamber disposed upwardly of, and offset horizontally from, said inlet port, said discharge chamber having a lower wall and an outlet port near said lower wall, said outlet port being above said inlet port; guide means extending from adjacent the low end of said collection tank to said discharge chamber, said guide means being open at its lower end and communicating with said tank so that sewage materials may enter thereinto from said tank; an inclined endless flexible flight conveyor having a lower, upwardly movable course extending between the low end of said collection tank and said discharge chamber, said upwardly moving course being movable along said guide means to move sewage to said discharge chamber, said conveyor having an upper, downwardly movable extending course above said upwardly movable course and a curved portion connecting said upwardly and downwardly movable courses, said downwardly movable course extending downwardly through said collection tank and being spaced vertically upwardly from said upwardly movable course and said inlet port a substantial distance, said curved portion being disposed outwardly of said collection tank, and the low part of said curved portion being below said bottom wall and said curved portion extending upwardly through said bottom wall; a tubular casing enclosing and guiding said curved portion of said conveyor; and means for driving said conveyor.

5. An apparatus according to claim 4 wherein said flight conveyor is a flexible chain having a plurality of uniformly spaced, circular, substantially identical disks mounted on said chain; said conduit being an upwardly inclined, substantially semi-circular trough for snugly engaging a portion of the periphery of said disks, said s i char e ham e f n apparatus for raising sewage materials from a lower pipe to a higher sewer pipe, comprisingi a fluid-' tight housing; partition means within said hanging irig' a collecfion tank in'tl' elower portionthere f, sai d having a downwardly inclined bottom'w'all" and having aninlet port communicating with said lower sewer pipe; partition means within said housing defining a discharge chamber in the upper portion thereof and offset horizontally from said collection tank, said discharge chamber having a lower wall above said inlet port and having an outlet port adjacent said lower wall communicating with said higher sewer pipe; an endless flexible flight conveyor having inclined upwardly and downwardly movable courses within said housing, said upwardly movable course extending from said bottom wall to said discharge chamber and being positioned below said downwardly movable course; conduit means within said housing and extending upwardly from adjacent said bottom wall to said discharge chamber, said conduit being open at its lower end so that sewage materials in said collection tank may enter thereinto, the flights of the lower, upwardly movable course of said conveyor being received in said conduit for upward movement therethrough, said conveyor having a reversely curved portion connecting said upper and lower courses, said upper course extending downwardly through said housing and being spaced vertically upwardly from said lower course and said inlet port so that it is above the normal level of sewage materials in said collection tank, said curved portion being disposed outwardly of said housing and including an upwardly moving section whose lowermost point is disposed below said bottom wall, said upwardly moving portion extending through said bottom wall whereby said conveyor moves upwardly through said bottom wall; a tubular, reversely curved casing enclosing and guiding said curved portion of said conveyor, the cross-sectional shape of said casing being substantially the same throughout its length; and rotatable sprocket means for driving said conveyor, said sprocket means drivingly engaging said conveyor only at the upper end thereof.

7. The structure of claim 4 wherein said tank has a bottom wall which slopes downwardly away from said inlet port to said low end of said tank; and said upwardly movable course of said flight conveyor passes through an opening in said bottom wall adjacent to said low end.

8. The structure of claim 4 wherein said flight conveyor includes a plurality of substantially uniformly spaced, identical and circular disks; and said conduit includes a tube communicating between said low end and said chamber and having an internal surface along at least a portion of said tube with a circular cross-section making a close, sliding, clearance with respect to said disks, said portion of said tube substantially longer than the center line distance between a pair of adjacent disks.

9. The structure of claim 4 wherein said flight conveyor is comprised of a link chain having a plurality of uniformly spaced, substantially identical and circular disks mounted thereon; said conduit means is comprised of a cylindrical tube extending between said collection tank and said chamber and surrounding the part of said upwardly moving course therebetween, at least the lower portion of said tube having an inside diameter substantially equal to the diameter of said disks for a distance along said tube substantially greater than the distance between a pair of adjacent disks.

10. The structure of claim 4 wherein said flight conveyor is comprised of a flexible chain and a plurality 15 of uniformly spaced, circular and substantially identical disks mounted upon said chain; said discharge chamber is contained within a housing spaced substantially from said tank; said conduit means is comprised of a cylindrical tube communicating between said bottom wall and said chamber, at least a portion of said tube near to said bottom wall having an internal diameter substantially equal to the diameter of said disks for a distance in excess of References Cited in theme of this patent UNITED STATES PATENTS Burwell Feb. 11,1879 ;McDonald Jan. 17, 1905 Cunning Aug. 10, 1909 Whitlock Oct. 5, 1909 Hathaway Sept. 5, 1911 Merwin June 2, 1914 Andrews Apr. 3, 1917 Neely Dec. 4, 1945 FOREIGN PATENTS Italy Dec. 5, 1951 

